A scheme to repair the beam has already been developed, with a contractor in place to carry out the work and all of the materials delivered to site. Caltrans said yesterday that it would be a challenge to carry out the repair before tomorrow's planned reopening of the bridge but that it will be doing everything possible to meet the schedule.

The bridge had been closed for the weekend to allow work as part of the US state's extensive seismic retrofit programme. Work to remove a 91m-long, 3,200t section has been going well and is on schedule for completion by the planned reopening time early tomorrow. However, the discovery of the unrelated crack may now delay the reopening.